Three Dimensional Optical Imaging of Neptunium Redox Speciation-A Feasibility Study

镎氧化还原形态的三维光学成像-可行性研究

• 批准号: EP/R001499/1
• 负责人: Louise Natrajan
• 金额: $ 24.98万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FR001499%2F1
• 关键词: Three; Dimensional; Optical; Imaging; Neptunium

One of the most pressing problems facing society today is the management of existing and future waste forms arising from nuclear energy production. Here, the redox chemistry of the actinide elements plays a crucial role in many aspects of nuclear fission including safe disposal strategies and new recovery and recycling routes. Understanding the chemistry of actinides in engineered environments is imperative for the management of existing and future fission products (nuclear waste) arising from nuclear power production, particularly for underground geological disposal. In particular, the redox chemistry of neptunium, a key radionuclide found in appreciable quantities in high level waste is complex, changeable and currently not well understood. Over the lifespan of the proposed geological disposal facility, one of the principal hazards is a change in chemistry of neptunium that may result in leaching from the repository, breaching primary containment and entering the engineered environment. Due to the particular complex redox and chemical speciation of neptunium, crucial mechanistic information on redox chemistry and speciation that affects its interactions with engineered and natural encapsulating materials including the host rock and backfill material is lacking and remains one of the principal chemical challenges facing this field. In this feasibility study, we will address the prospect of using one and two photon fluorescence and phosphorescence spectroscopy and microscopy as a non-destructive technique to address this problem. We aim to visualise, locate and spatially map the different oxidation states of neptunyl that can co-exist in solution in model conditions using well defined complexes and aqua ions in with the ubiquitous geologically relevant minerals silica, alumina and calcite at previously unseen levels of detail (sub micrometer resolution). We have recently demonstrated that neptunyl(V) and (VI) emission occurs in the green and blue regions of the electromagnetic spectrum and are equally as intense as the uranyl(VI) ion, whose optical properties are well known and have been used by us for fluorescence and phosphorescence microscopy imaging. This means that both oxidation states can be detected simultaneously so that highly sensitive, informative three-dimensional imaging can be used to understand neptunyl geochemistry below the micron scale. This will add much needed important information to the safety case for nuclear waste disposal in a range of heterogeneous systems.

当今社会面临的最紧迫的问题之一是对核能生产中产生的现有和未来废物形式的管理。在这里，锕系元素的氧化还原化学在核裂变的许多方面发挥着至关重要的作用，包括安全处置策略和新的回收和再循环路线。了解工程环境中锕系元素的化学性质对于管理核电生产中产生的现有和未来裂变产物（核废物）至关重要，特别是地下地质处置。特别是，镎（一种在高放废物中大量存在的关键放射性核素）的氧化还原化学非常复杂、多变，目前尚不清楚。在拟议的地质处置设施的使用寿命期间，主要危险之一是镎的化学变化，这可能导致镎从处置库中浸出，破坏主要安全壳并进入工程环境。由于镎特殊复杂的氧化还原和化学形态，影响其与工程和天然封装材料（包括主岩和回填材料）相互作用的氧化还原化学和形态的关键机制信息缺乏，并且仍然是该领域面临的主要化学挑战之一。在这项可行性研究中，我们将探讨使用一光子和二光子荧光和磷光光谱以及显微镜作为非破坏性技术来解决这一问题的前景。我们的目标是使用定义明确的络合物和水离子与普遍存在的地质相关矿物二氧化硅、氧化铝和方解石，以以前未见过的细节水平（亚微米分辨率），在模型条件下可视化、定位和空间绘制可以在溶液中共存的庚烷的不同氧化态。我们最近证明，庚烯基 (V) 和 (VI) 发射发生在电磁波谱的绿色和蓝色区域，并且与铀酰 (VI) 离子一样强烈，其光学特性众所周知，并已被我们用于荧光和磷光显微镜成像。这意味着可以同时检测两种氧化态，从而可以使用高度灵敏、信息丰富的三维成像来了解微米级以下的海王基地球化学。这将为一系列异构系统中核废料处置的安全案例添加急需的重要信息。

项目成果

Synthesis of Unsymmetrical Diboron(5) Compounds and Their Conversion to Diboron(5) Cations

不对称二硼(5)化合物的合成及其转化为二硼(5)阳离子

• DOI: 10.1021/acs.organomet.8b00288
• 发表时间: 2018
• 期刊: Organometallics
• 影响因子: 2.8
• 作者: Cid J